Tetravinyl-unsaturated resin paint composition and painting process

ABSTRACT

A SUBSTRATE IS COATED WITH A FILM-FORMING COMPOSITION CONSISTING ESSENTIALLY OF A UNIQUE TETRAVINYL COMPOUND HAVING A MOLECULAR WEIGHT BELOW ABOUT 350, PREFERABLY IN THE RANGE OF ABOUT 220 TO ABOUT 1,1100, AND AN ALPHABETA OLEFINICALLY UNSATURATED PAINT BINDER RESIN HAVING A MOLECULAR WEIGHT IN EXCESS OF ABOUT 1,000, PREFERABLY IN THE RANGE OF ABOUT 2,000 TO ABOUT 20,000, IS CONVERTED INTO A TENACIOUSLY ADHERING, SOLVENT-RESISTANT, WEAR AND WEATHER-RESISTANT COATING BY EXPOSING THE COATED SUBSTRATE TO IONIZING RADIATION, PREFERABLY IN THE FORM OF AN ELECTRON BEAM. THIS TETRAVINYL COMPOUND IS FORMED BY FIRST REACTING A DIEPOXIDE WITH ACRYLIC ACID AND/OR METHACRYLIC ACID AND SUBSEQUENTLY REACTING THE RESULTANT ESTER CONDENSATION PRODUCT WITH A VINYL UNSATURATED ACYL HALIDE.

United States Patent ABSTRACT OF THE DISCLOSURE A substrate is coatedwith a film-forming composition consisting essentially of a uniquetetravinyl compound having a molecular weight below about 350,preferably in the range of about 220 to about 1,100, and an alphabetaolefinically unsaturated paint binder resin having a molecular weight inexcess of about 1,000, preferably in the range of about 2,000 to about20,000, is converted into a tenaciously adhering, solvent-resistant,wear and weather-resistant coating by exposing the coated substrate toionizing radiation, preferably in the form of an electron beam. Thistetravinyl compound is formed by first reacting a diepoxide with acrylicacid and/or methacrylic acid and subsequently reacting the resultantester condensation product with a vinyl unsaturated acyl halide.

This invention relates to the art of coating. It is particularlyconcerned with a process of painting a substrate having externalsurfaces of wood, glass, metal or polymeric solid with a film-formingsolution comprising unique tetravinyl compounds and an alpha-betaolefinically unsaturated paint binder resin and crosslinking suchfilmforming solution into a wear-resistant, weather-resistant,solventresistant, tenaciously adhering film by exposing the same toionizing radiation, preferably in the form of an electron beam, and tothe paint used in this process.

In this application, the term paint is meant to include pigment and/orfinely ground filler, the binder without pigment and/or filler or havingvery little of the same, which can be tinted if desired. Thus, the paintbinder which is ultimately crosslinked by ionizing radiation can be allor virtually all that is used to form the film, or it can be a vehiclefor pigment and/or particulate filler material.

The first reaction step in preparing the tetravinyl compounds usedherein is illustrated by the representative reaction shown in FIG. 1 ofthe accompanying drawing. The second reaction step is illustrated by therepresentative reaction shown in FIG. 2.

The diepoxides employed as starting materials for preparing thetetravinyl compounds of this invention may be of theepichlorohydrin-bisphenol type, the epichlorohydrin-polyalcohol type, orthose prepared by reacting diolefins with peracides, e.g., peraceticacid, or other means. Diepoxides and their preparation are discussed indetail in Modern Surface Coatings, Paul Nylen and Edward Sunderland,1965 Science Publishers, a division of John Wiley & Sons Ltd.,London-New York-Sydney, Library of Congress Catalog Card Number65-28344, pp. 197-208. Representative diepoxides include, but not by wayof limitation the following:

(1) 3,4-epoxy-6-methyl-cyclohexylmethyl 3,4epoxymethylcyclohexanecarboxylate.

(2) 1-epoxyethyl-3,4-epoxycyclohexane.

(3) Dipentene dioxide (limonene dioxide).

(4) Dicyclopentadienedioxide.

(5) Diepoxides having structural formula in accord- Other suitablediepoxides are disclosed in US. Pats. 2,890,202; 3,256,226; 3,373,221and elsewhere throughout the literature.

The diepoxides employed will usually have molecular Weights below about2,000, more commonly in the range of about to about 500. Usually, thediepoxides will consist of carbon, hydrogen and oxygen but they may besubstituted, if desired, with non-interfering substituents, such ashalogen atoms, ether radicals and the like. They may be saturated orunsaturated, aliphatic, cycloaliphatic, aromatic or heterocyclic. Theymay be monomeric or polymeric.

The vinyl unsaturated acyl halides are preferably acryloyl chloride and/or methacryloyl chloride but others may be used, e.g., the correspondingbromides.

The resultant tetravinyl compounds used herein are homopolymerizable andcopolymerizable with monoand divinyl monomers, e.g., styrene, vinyltoluene, alphamethyl styrene, divinyl benzene, methyl methacrylate,

ethyl acrylate, butyl acrylate, butyl methacrylate, hydroxypropylmethacrylate, glycidyl methacrylate, etc., the divinyl reaction productformed by reacting a monoepoxide with acrylic acid or methacrylic acidand then reacting the resultant ester condensation product with a vinylunsaturated acyl halide, the divinyl reaction product formed by reactinga diepoxide with two molar parts of acrylic acid or methacrylic acid,the divinyl reaction product formed by reacting a diepoxide with twomolar parts of acrylic acid or methacrylic acid and subsequentlyreacting the resultant ester condensation prodnet with two molar partsof a saturated acyl halide, e.g., acetyl chloride, or an effectivelysaturated acyl halide, e.g., benzoyl chloride, the divinyl reactionproduct formed by reacting one molar part of a diepoxide with two molarparts of acrylic acid or methacrylic acid and subsequently reacting theresultant ester condensation product with two molar parts of analpha-beta olefinically unsaturated acyl halide having an aromaticradical affixed to the beta carbon of the olefinic linkage, e.g.,cinnamic acid chloride, alpha-beta olefinically unsaturated polymers,etc.

The tetravinyl adducts used herein have lower viscosities than theircorresponding divinyl compounds produced by reacting one mole ofdiepoxide with two moles of acrylic or methacrylic acid. In relation tosuch divinyl compounds, the tetravinyl compounds are also more sensitiveto ionizing radiation and have increased solubility in organic solvents.

The alpha-beta olefinically unsaturated paint binder resins havemolecular weights in excess of about 1,000, preferably in the range ofabout 2,000 to about 20,000. They consist essentially of carbon,hydrogen and oxygen but they may be substituted, if desired, withnon-interfering substituents, such as halogen atoms, nitrogen atoms,ether radicals and the like. They advisedly have their alpha-betaolefinic unsaturation concentration limited to about 0.5 to about 5,preferably about 0.7 to about 3, units per 1,000 units molecular weight.Preferably, they are either polyesters or vinyl monomer comprisingcopolymers. Suitable alpha-beta unsaturated resins are disclosed in U.S.Pats. 3,437,512; 3,437,513 and 3,437,514.

In accordance with this invention, the paint binder composition,exclusive of nonpolymerizable solvents, pigments and particulate mineralfiller, consists essentially of to about 80, preferably about to about60 parts by weight of the tetravinyl compound and about 90 to about 20,preferably about 80 to about 40, parts by weight of the alpha-betaolefinically unsaturated resin.

It is within the scope of this invention to replace a minor portion,i.e., up to slightly below about 50 weight percent of the tetravinylcompound and/ or the alpha-beta olefinically unsaturated resins withmonovinyl monomers and/or a divinyl compound consisting essentially ofcarbon, hydrogen and oxygen and having a molecular weight below about2,600, preferably about 220 to about 1,100, more preferably about 220 toabout 650 such as one of the divinyl compounds hereinbefore mentionedand hereinafter exemplified.

The films formed from the paints of this invention are advantageouslycured at relatively low temperatures, e.g., between room temperature (20to C.) and the temperature at which significant vaporization of its mostvolatile component is initiated, ordinarily between 20 and 70 C. Theradiation energy is applied at dose rates of about 0.1 to about 100 Mradper second upon a preferably moving workpiece until the wet film isconverted to tack-free state or until the film is exposed to a desireddosage.

The film-forming material advisedly has an application viscosity lowenough to permit rapid application to the substrate in substantiallyeven depth and high enough so that at least 1 mil (0.001 inch) film willhold upon a vertical surface without sagging. Such 'filrns willordinarily be applied to an average depth of about 0.1 to about 4 milswith appropriate adjustment in viscosity and application technique. Itwill be obvious to those skilled in the art that the choice of diepoxideused in preparing the tetravinyl compound can be varied so as to varythe viscosity of the resultant product. Likewise, the viscosity of thetotal film-forming composition can be varied by the concentration andchoice of vinyl monomers or other polymerizable components of thecoating composition such as the aforementioned resins. The viscosity canalso be adjusted by the addition of nonpolymerizable, volatile solvents,e.g., toluene, xylene, acetone, etc., which can be flashed off afterapplication. By one or more of such adjustments, the viscosity of thepaint binder solution can be adapted for application by conventionalpaint application techniques, e.g., spraying, roll coating, etc. Thepaint binder is preferably applied to the substrate and cured thereon asa continuous film of substantially even depth.

This invention will be more fully understood from the followingillustrative examples.

4 EXAMPLE 1 A tetravinyl compound is prepared in the manner below setforth from the materials hereinafter named:

(1) To a reaction vessel equipped with condenser, stirrer, nitrogeninlet and thermometer are charged the following materials:

Parts by weight (a) Diepoxide 192 (b) Methacrylic acid 86 (c) Toluene(solvent) 500 (d) Dimethyl benzylamine (catalyst) 1 i F I i i-ti y-x E-r? r H H H (13:? CH3 (|3=(|3 H H H H H H H (2) The diepoxide, themethacrylic acid and the dimethyl benzylamine are intimately mixed andincrementally -added to the toluene which is at 90 C. in a nitrogenatmosphere.

(3) The reaction mixture is maintained at 90 C. until reaction of theepoxide groups is essentially complete as measured by a product acidnumber of less than about 10.

(4) The solvent is removed under vacuum and a solid reaction product(softening point 45 C.) is recovered.

(1) The solid reaction product of (4) in the amount of 280 parts byweight is dissolved in 500 parts by Weight toluene, parts by Weight ofmethacryloyl chloride are added dropwise with the reaction mixturemaintained at 65 C. until HCl evolution ceases.

(6) The solvent is removed under vacuum and a tetravinyl compound isrecovered in the form of a viscous liquid.

An alpha-beta olefinically unsaturated vinyl resin, Res n A, is preparedin the following manner:

Starting materials: Parts by weight Xylene 600 Methyl methacrylate 196Ethyl acrylate 333 Glycidyl methacrylate 71 Azobisiso butyronitrile 6Hydroquinone 0.12 Methacrylic acid 42 Triethyl amine 0.96

Procedure The solvent, xylene, is charged to a flask fitted with astirring rod, an additional funnel, a thermometer, a nitrogen inlet tubeand a condenser. The amount of xylene is equal to the total weight ofvinyl monomers to be added. The xylene is heated to reflux, nitrogen isbubbled through the solution during heat up and throughout the reaction.The combined monomers, excepting the methacrylic acid, and initiator(azobisiso butyronitrile) is added to the re fluxing solution evenlyover a two-hour period. The initiator weight is 10 parts by weight per1,000 parts by Weight of vinyl monomers. The reaction solution isrefluxed until the conversion of monomer to polymer is greater thanabout 97 percent.

In the second step, hydroquinone is added as an inhibitor and then themethacryiic acid is added to react with the epoxy groups on the polymer.Triethyl amine is used as a catalyst. This esterification reaction iscarried out at reflux temperatures until about 80 percent esterificationis accomplished (determined by residual acid number). The xylene is thenremoved by vacuum distillation and the polymer dissolved in methylmethacrylate so that the weight ratio of polymer to solvent is two.

Substrates of wood, metal and polymeric solid, i.e., polypropylene andacrylonitrile-butadiene-styrene copolymer, are coated with a paintbinder consisting essentially of this tetravinyl compound and Resin Ausing the following procedure:

(1) Twenty (20) parts by weight of the tetravinyl compound is mixed with80 parts by weight of Resin A and diluted to spraying viscosity withacetone. This solution is sprayed upon the aforementioned substrates toan average depth of about 1 mil (0.001 inch) and the solvent flashedoff. The coated substrate is passed through a nitrogen atmosphere and ata distance of about .10 inches below the electron emission window of acathode ray type, electron accelerator through which an electron beam isprojected upon the coated surface until the wet coating is polymerizedto a tack-free state. The electrons of this beam have an average energyof about 275,000 volts with a current of about 25 milliamperes.

(2) A second group of substrates are coated in the manner above setforth using the same conditions and materials except for the singledifierence that the paint binder solution used consists of 60 parts byweight of the tetravinyl compound, 40 parts by weight of Resin A, andsaid acetone.

(3) A third group of substrates are coated in the manner above set forthusing the same conditions and materials except for the single differencethat the paint binder solution used consists of 10 parts by weight ofthe tetravinyl compound, 90 parts by weight of Resin A, and saidacetone.

(4) A fourth group of substrates are coated in the manner above setforth using the same conditions and materials except for the singledifference that the paint binder solution used consists of 80 parts byweight of the tetravinyl compound, 20 parts by weight of Resin A, andsaid acetone.

EXAMPLE 2 The procedure of Example 1 is repeated with the followingdifferences: (1) Resin A is replaced with a polyester resin, Resin Bhereinafter described, (2) the irradiation atmosphere is helium, and (3)the electron beam used has an average energy of about 350,000 electronvolts.

Preparation of Resin B Starting materials: Parts by weight Maleicanhydride 14.7

Tetrahydrophthalic anhydride 72.3

Neopentyl glycol 75.0

Dibutyl tin oxide, catalyst 7.06

Procedure To a reaction vessel, the reactants are charged and thenheated to about 340 F. and held at this temperature for one hour. Thetemperature of the charge is then raised to 440 F. and maintained atsuch temperature until the acid number of the resulting resin is belowabout 20. The excess glycol and water are removed by vacuum and when theacid number is below about 10, there are added 0.03 part by weighthydroquinone.

EXAMPLE 3 The procedure of Example 2 is repeated with the soledifference that Resin B is replaced with an equal amount by weight ofResin C, a polyester prepared by the procedure used to prepare Resin Bexcept that an equimolar amount of phthalic anhydride is substituted forthe tetrahydrophthalic anhydride.

EXAMPLE 4 The procedure of Example 2 is repeated with the soledifference that Resin B is replaced with an equal amount by weight ofResin D, a polyester prepared by the procedure used to prepare Resin Bexcept that an equimolar amount of ethylene glycol is substituted forthe neopentyl glycol.

EXAMPLE 5 The procedure of Example 2 is repeated with the soledifierence that Resin B is replaced with an equal amount 6 by weight ofResin E, a polyester prepared by the procedure used to prepare Resin Bexcept that an equimolar amount of trimellitic anhydride is substitutedfor the tetrahydrophthalic anhydride.

EXAMPLE 6 The procedure of Example 2 is repeated with the soledifference that Resin B is replaced with an equal amount by weight ofResin F, a polyester prepared by the procedure used to prepare Resin Bexcept that an equimolar amount of pentaerythritol is substituted forthe tetrahydrophthalic anhydride.

EXAMPLE 7 The procedure of Example 2 is repeated with the soledifference that Resin B is replaced with an equal amount by weight ofResin G, a polyester prepared by the procedure used to prepare Resin Bexcept that an equimolar amount of 1,6-hexamethylene glycol issubstituted for the neopentyl glycol.

EXAMPLE 8 The procedure of Example 2 is repeated with the soledilference that Resin B is replaced with an equal amount by weight ofResin H, a polyester prepared by the procedure used to prepare Resin Bexcept that an equimolar amount of fumaric acid is substituted for themaleic anhydride.

EXAMPLE 9 The procedure of Example 2 is repeated with the soledifference that Resin B is replaced with an equal amount by weight ofResin I, a polyester prepared by the procedure used to prepare Resin Bexcept that an equimolar amount of 2-butene-l,4-diol is substituted forthe neopentyl glycol.

EXAMPLE 10 The procedures of Examples 1 and 2 are repeated in thoseembodiments wherein a nonpolymerizable solvent is employed with the soledifference that the acetone is replaced by toluene.

EXAMPLE 11 The procedure of Example 1 is repeated with the soledilference that Resin A is replaced with a diiferent vinyl monomercomprising resin, Resin J.

Preparation of Resin I Starting materials: Parts by weight Methylmethacrylate 400 Ethyl acrylate 400 Hydroxy ethyl methacrylate 195Toluene 105,18

Benzoyl peroxide Procedure Step II.

Parts by weight Solution from Step I 500 Acryloyl chloride 33.8 Toluene30 The solution of Step I is heated to 60 C. and a solu tion of theacryloyl chloride and toluene are added dropwise over a four hour periodwhile the temperature is allowed to rise to about C.

After heating for another 2.5 hours, the polymer is recovered by vacuumdistillation.

7 EXAMPLE 12 The procedure of Example 1 is repeated with the soledifference that Resin A is replaced with a different vinyl monomercomprising resin, Resin K.

Preparation of Resin K Starting materials: Parts by weight Procedurewith the following materials:

Step II. Parts by weight Copolymer from Step I, in xylene 69 Allylglycidyl ether Potassium hydroxide A solution of the allyl glycidylether and potassium hydroxide is added to the copolymer at roomtemperature. The mixture is then heated to a temperature of about 100l20C. This temperature is maintained for about 7 hours and allowed to cool.The polymeric reaction product is separated from xylene by vacuumdistillation.

EXAMPLE 13 The procedure of Example 1 is repeated except that thediepoxide employed is 3,4-epoxy-6-methylcyclohexylmethyl-3,4-epoxymethyl-cyclohexanecarboxylate.

EXAMPLE 14 The procedure of Example 2 is repeated except that thediepoxide employed is 1-epoxyethyl-3,4-epoxycyclohexane.

EXAMPLE 15 The procedure of Example 1 is repeated except that thediepoxide employed is dipentene dioxide.

EXAMPLE 16 The procedure of Example 2 is repeated except that thediepoxide employed is dicyclopentadienedioxide.

EXAMPLE 17 The procedure of Example 1 is repeated except that thediepoxide employed has structural formula in accordance with the formulahereinbefore set forth and identified as diepoxide ()a wherein n is 4.

EXAMPLE 18 The procedure of Example 2 is repeated except that thediepoxide employed has structural formula in accordance with the formulahereinbefore set forth and identified as diepoxide (5 )b.

EXAMPLE 19 The procedure of Example 1 is repeated except that thediepoxide employed has structural formula in accordance with the formulahereinbefore set forth and identified as diepoxide (5)c wherein n is 4.

8 EXAMPLE 20 The procedure of Example 1 is repeated with the soledifference that methacryloyl bromide is used in lieu of methacryloylchloride.

EXAMPLE 21 The procedure of Example 1 is repeated with the soledlfiference that acryloyl chloride is substituted for the methacryloylchloride.

EXAMPLE 22 The procedure of Example 1 is repeated with the soledifference that acryloyl bromide is substituted for the methacryloylchloride.

EXAMPLE 23 The procedure of Example 1 is repeated with the soledifference that the diepoxide is first reacted with a mixture of acrylicacid and methacrylic acid and subsequently reacted with the methacryloylchloride.

EXAMPLE 24 A tetravinyl compound is prepared as in Example 1 and adivinyl compound is prepared using the same procedure with the singleexception that butyric acid chloride is substituted for the second stepreactant methacryloyl chloride used in the preparation of the tetravinylcompound. Substrates are then coated as in Example 1 with the soledifference that in the paint binder solution 49 weight percent of thetetravinyl compound is replaced with an equal amount by weight of saiddivinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 1 weight percent of the tetravinyl compound is replacedwith an equal amount by weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 25 weight percent of the tetravinyl compound is replacedwith an equal amount by weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 1 weight percent of Resin A is replaced with an equalamount by weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 25 Weight percent of Resin A is replaced with an equalamount by weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 49 weight percent of Resin A is replaced with an equalamount by weight of said divinyl compounds.

EXAMPLE 25 A tetravinyl compound is prepared as in Example 1 and adivinyl compound is prepared using the same procedure with the singleexception that cinnamic acid chloride is substituted for the second stepreactant methacryloyl chloride used in preparation of the tetravinylcompound. Substrates are then coated as in Example 1 with the soledifference that in the paint binder solution 49 weight percent of thetetravinyl compound is replaced with an equal amount by weight of saiddivinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 1 weight percent of the tetravinyl compound is replacedwith an equal amount by Weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 25 weight percent of the tetravinyl compound is replacedwith an .equal amount by weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 1 weight percent of Resin A is replaced with an equalamount by weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 25 weight percent of Resin A is replaced with an equalamount by weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 49 weight percent of Resin A is replaced with an equalamount by weight of said divinyl compound.

EXAMPLE 26 A tetravinyl compound is prepared as in Example 1 and adivinyl compound is prepared using the same procedure with the singleexception that 1 molar part of cyclopentene oxide is reacted with 1molar part of methacrylic acid to open the epoxide ring and provide amonovinyl compound and with one molar part of methacryloyl chloride atthe hydroxyl resulting from the first reaction to provide a divinylcompound. Substrates are then coated as in Example 1 with the soledifference that in the paint binder solution 49 weight percent of thetetravinyl compound is replaced with an equal amount by weight of saiddivinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 1 Weight percent of the tetravinyl compound is replacedwith an equal amount by weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 25 weight percent of the tetravinyl compound is replacedWith an equal amount by weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 1 weight percent of Resin A is replaced with an equalamount by weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 49 weight percent of Resin A is replaced with an equalamount by weight of said divinyl compound.

EXAMPLE 27 A tetravinyl compound is prepared as in Example 1 and adivinyl compound is prepared using the same procedure employed in thefirst step of preparing the tetravinyl compound. Substrates are coatedas in Example 1 with the sole difference that in the paint bindersolution 49 weight percent of the tetravinyl compound is replaced withan equal amount by weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 1 weight percent of the tetravinyl compound is replacedwith an equal amount by weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 25 weight percent of the tetravinyl compound is replacedwith an equal amount by weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 1 weight percent of Resin A is replaced with an equalamount by weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 25 weight percent of Resin A is replaced with an equalamount by weight of said divinyl compound.

Additional substrates are coated in like manner except that in the paintbinder solution 49 weight percent of Resin A is replaced with an equalamount by weight of said divinyl compound.

EXAMPLE 28 The procedure of Example 24 is repeated except for the soledifference that benzoyl chloride is substituted for butyric acidchloride.

10 EXAMPLE 29 The procedures of Examples 24, 25, 26, 27 and 28 arerepeated except that the polyester resin, Resin B, is substituted forthe vinyl resin, Resin A.

EXAMPLE 3 0 The procedure of Example 1 is repeated except that 49 Weightpercent of the tetravinyl compound is replaced with an equal amount byweight of monovinyl monomers, i.e., methyl methacrylate, ethyl acrylate,butyl methacrylate and Z-ethyl-hexyl acrylate.

EXAMPLE 31 The procedure of Example 1 is repeated except that 25 weightpercent of the tetravinyl compound is replaced with an equal amount byweight of monovinyl monomers, i.e., methyl methacrylate, butyl acrylateand styrene in an equimolar mixture.

EXAMPLE 3 3 The procedure of Example 1 is repeated except that 49 weightpercent of Resin A is replaced with an equal amount by weight ofmonovinyl monomers, i.e., methyl methacrylate, ethyl acrylate, butylmethacrylate and 2-ethylhexyl acrylate.

EXAMPLE 34 The procedure of Example 1 is repeated except that 1 weightpercent of Resin A is replaced with an equal amount by weight ofmonovinyl monomers, i.e., methyl methacrylate and styrene in anequimolar mixture.

EXAMPLE 35 The procedure of Example 1 is repeated except that 25 weightpercent of Resin A is replaced with an equal amount by weight ofstyrene.

EXAMPLE 36 The procedure of Example 2 is repeated except that 49 weightpercent of the tetravinyl compound is replaced with an equal amount byweight of monovinyl monomers, i.e., methyl methacrylate, alpha-methylstyrene, butyl acrylate and ethyl acrylate.

EXAMPLE 37 The procedure of Example 2 is repeated except that 1 weightpercent of the tetravinyl compound is replaced with an equal amount byweight of monovinyl monomers, i.e., methyl methacrylate.

EXAMPLE 3 8 The procedure of Example 2 is repeated except that 25 Weightpercent of the tetravinyl compound is replaced with an equal amount byweight of monovinyl monomers, i.e., methyl methacrylate, hydroxyethylmethacrylate and ethyl acrylate in equimolar amounts.

EXAMPLE 39 The procedure of Example 2 is repeated except that 49 Weightpercent of Resin B is replaced with an equal amount by weight of methylmethacrylate.

EXAMPLE 40' The procedure of Example 2. is repeated except that 1 weightpercent of Resin B is replaced with an equal amount by weight of methylmethacrylate.

EXAMPLE 41 The procedure of Example 2 is repeated except that 25 weightpercent of Resin B is replaced with an equal amount by weight ofstyrene.

EXAMPLE 42 The procedure of Example 1 is repeated except that 25 Weightpercent of the tetravinyl compound and 25 weight percent of Resin A arereplaced with an equal amount by weight of an equimolar mixture ofstyrene and methyl methacrylate.

EXAMPLE 43 The procedure of Example 2 is repeated except that 25 weightpercent of the tetravinyl compound and 25 weight percent of Resin -B arereplaced with an equal amount by weight of an equimolar mixture ofstyrene and methyl methacrylate.

The term ionizing radiation as employed herein means radiation havingsufficient energy to elfect polymerization of the paint films hereindisclosed, i.e., energy equivalent to that of about 5,000 electron voltsor greater. The preferred method of curing films of the instant paintsupon substrates to which they have been applied is by subjecting suchfilms to a beam of polymerization effecting electrons having an averageenergy in the range of about 100,000 to about 500,000 electron volts.When using such a beam, it is preferred to employ a minimum of 25,000electron volts per inch of distance between the radiation emitter andthe workpiece when the intervening space is occupied by air. Adjustmentcan be made for the relative resistance of the intervening gas which ispreferably an oxygen-free inert gas such as nitrogen or helium.

The abbreviation rad as employed herein means that dose of radiationwhich results in the absorption of 100 ergs of energy per gram ofabsorber, e.g. coating film. The abbreviation Mrad as employed hereinmeans 1 million rad. The electron emitting means may be a linearelectron accelerator capable of producing a direct current potential inthe range of about 100,000 to about 500,000 volts. In such a deviceelectrons are ordinarily emitted from a hot filament and acceleratedthrough a uniform voltage gradient. The electron beam, which may beabout Ms inch in diameter at this point, may then be scanned to make afanshaped beam and then passed through a metal window, e.g., amagnesium-thorium alloy, aluminum, an alloy of aluminum and a minoramount of copper, etc., of about 0.003 inch thickness.

It will be understood by those skilled in the art that modifications canbe made within the foregoing examples without departing from the spiritand scope of the invention as set forth in the following claims.

What is claimed is:

1. A paint polymerizable by ionizing radiation which, exclusive ofnonpolymerizable solvents, pigments and particulate mineral filler,consists essentially of a film-forming solution of about 20 to about 90parts of an alpha-beta olefinically unsaturated resin having molecularweight in excess of about 1,000 and about 80 to about 10- parts byweight of a tetravinyl compound formed by first reacting one molar partof a diepoxide with two molar parts of an alpha-beta olefinicallyunsaturated monocarboxylic acid selected from acrylic acid andmethacrylic acid and subsequently reacting the resultant divinyl estercondensation product with two molar parts of a vinyl unsaturated acylhalide.

2. A paint in accordance with claim 1 wherein said diepoxide has amolecular weight below about 2,000.

3-. A paint in accordance with claim 1 wherein said diepoxide has amolecular weight in the range of about 140 to about 500.

4. A paint in accordance with claim 1 wherein said alpha-betaolefinically unsaturated resin contains about 0.5 to about 5 units ofalpha-beta olefinic unsaturation units per 1,000 units molecular weightand has a molecular weight in the range of about 2,000 to about 20,000.

5. A paint in accordance with claim 1 wherein said alpha-betaolefinically unsaturated resin contains about 0.7 to about 3 units ofalpha-beta olefinic unsaturation per 1,000 units molecular weight andhas a molecular weight in the range of about 2,000 to about 20,000 andsaid diepoxide compound has a molecular weight in the range of about 140to about 500.

6. A paint in accordance with claim 1 wherein said acyl halide is thechloride of acrylic or methacrylic acid.

7. A paint in accordance with claim 1 wherein said acyl halide is thebromide of acrylic or methacrylic acid.

8. A paint in accordance with claim 1 wherein an amount up to but lessthan 50% of said alpha-beta olefinically unsaturated resin is replacedwith an equal amount by weight of a divinyl compound consistingessentially of carbon, hydrogen and oxygen and having a molecular weightbelow about 2,600.

9. A paint in accordance with claim 1 wherein an amount up to but lessthan 50% of said alpha-beta olefinically unsaturated resin is replacedwith an equal amount by weight of a divinyl compound consistingessentially of carbon, hydrogen and oxygen and having a molecular weightin the range of about 220 to about 1,100.

10. A paint in accordance with claim 1 wherein an amount up to but lessthan 50% of said alpha-beta olefinically unsaturated resin is replacedwith an equal amount by weight of monovinyl monomers.

11. A paint in accordance with claim 1 wherein an amount up to but lessthan 50% of said tetravinyl compound is replaced with an equal amount byweight of a divinyl compound consisting essentially of carbon, hydrogenand oxygen and having a molecular weight below about 2,600.

12. A paint in accordance with claim 1 wherein an amount up to but lessthan 50% of said tetravinyl compound is replaced with an equal amount byweight of a divinyl compound consisting essentially of carbon, hydrogenand oxygen and having a molecular weight in the range of about 220 toabout 1,100.

13. A paint in accordance with claim 1 wherein an amount up to but lessthan 50% of said tetravinyl compound is replaced with an equal amount byweight of monovinyl monomers.

14. A paint polymerizable by ionizing radiation which, exclusive ofnonpolymerizable solvents, pigments and particulate mineral filler,consists essentially of a filmforming solution of about 40 to aboutparts by weight of an alpha-beta olefinically unsaturated resin having amolecular weight in the range of about 1,000 to about 20,000 and about60 to about 20 parts by weight of a tetravinyl compound formed by firstreacting one molar part of a diepoxide having a molecular weight in therange of about to about 500 with two molar parts of an alpha-betaolefinically unsaturated monocarboxylic acid selected from acrylic acidand methacrylic acid and subsequently reacting the resultant divinylester condensation product with two molar parts of a vinyl unsaturatedacyl halide.

15. A paint in accordance with claim 14 wherein an amount up to but lessthan 50% of said tetravinyl compound is replaced with an equal amount byweight of a divinyl compound having a molecular weight in the range ofabout 220 to about 650 and formed by first reacting one molar part of adiepoxide with two molar parts of an alpha-beta olefinically unsaturatedmonocarboxylic acid selected from acrylic acid and methacrylic acid andsubsequently reacting the resultant ester condensation product with twomolar parts of a saturated acyl halide.

16. A paint in accordance with claim 14 wherein an amount up to but lessthan 50% of said alpha-beta olefinically unsaturated resin is replacedwith an equal amount by weight of a divinyl compound having a molec ularweight in the range of about 220 to about 650 and formed by firstreacting one molar part of a diepoxide with two molar parts of analpha-beta olefinically unsaturated monocarboxylic acid selected fromacrylic acid and methacrylic acid and subsequently reacting the re- 13sultant ester condensation product with two molar parts of a saturatedacyl halide.

17. A paint in accordance with claim 14 wherein an amount up to but lessthan 50% of said tetravinyl compound is replaced with an equal amount byweight of monovinyl monomers.

18. A paint in accordance with claim 14 wherein an amount up to but lessthan 50% of said alpha-beta olefinically unsaturated resin is replacedwith an equal amount by weight of monovinyl monomers.

19. A paint in accordance with claim 14 wherein an amount up to but lessthan 50% of said tetravinyl compound is replaced with an equal amount byweight of a divinyl compound having a molecular weight in the range ofabout 220 to about 650 and formed by first reacting one molar part of adiepoxide with two molar parts of an alpha-beta olefinically unsaturatedmonocarboxylic acid selected from acrylic acid and methacrylic acid andsubsequently reacting the resultant ester condensation product with twomolar parts of an alpha-beta olefinically unsaturated acyl halide havingan aromatic radical afiixed to the beta carbon of the olefinic linkage.

20. A paint in accordance with claim 14 wherein an amount up to but lessthan 50% of said alpha-beta olefinically unsaturated resin is replacedwith an equal amount by weight of a divinyl compound having a molecularweight in the range of about 220 to about 650 and formed by firstreacting one molar part of a diepoxide with two molar parts of analpha-beta olefinically unsaturated monocarboxylic acid selected fromacrylic acid and methacrylic acid and subsequently reacting theresultant ester condensation product with two molar parts of analpha-beta olefinically unsaturated acyl halide having an aromaticradical aifixed to the beta carbon of the olefinic linkage.

21. A paint in accordance with claim 14 wherein an amount up to but lessthan of said alpha-beta olefinically unsaturated resin is replaced withan equal amount by weight of a divinyl compound having a molecularweight in the range of about 220 to about 650 and formed by reacting onemolar part of a diepoxide with two molar parts of an alpha-betaolefinically unsaturated monocarboxylic acid selected from acrylic acidand methacrylic acid.

22. A paint in accordance with claim 14 wherein an amount up to but lessthan 50% of said tetravinyl compound is replaced with an equal amount byweight of a divinyl compound having a molecular weight in the range ofabout 220 to about 650 and formed by reacting one molar part of adiepoxide with two molar parts of an alpha-beta olefinically unsaturatedmonocarboxylic acid selected from acrylic acid and methacrylic acid.

23. A paint in accordance with claim 14 wherein an amount up to but lessthan 50% of said tetravinyl compound is replaced with an equal amount byweight of a divinyl compound having a molecular weight in the range ofabout 220 to about 650 and formed by reacting one molar part of adiepoxide with two molar parts of an alpha-beta olefinically unsaturatedmonocarboxylic acid selected from acrylic acid and methacrylic acid andsubsequently reacting the resultant ester condensation product with twomolar parts of an aromatic substituted saturated acyl halide.

24. A paint in accordance with claim 14 wherein an amount up to but lessthan 50% of said alpha-beta olefinically unsaturated resin is replacedwith an equal amount by weight of a divinyl compound having a molecularweight in the range of about 220 to about 650 and formed by reacting onemolar part of a diepoxide with two molar parts of an alpha-betaolefinically unsaturated monocarboxylic acid selected from acrylic acidand methacrylic acid and subsequently reacting the resultant 14 estercondensation product with two molar parts of an aromatic substitutedsaturated acyl halide.

25. A paint in accordance with claim 14 wherein an amount up to but lessthan 50% of said alpha-beta olefinically unsaturated resin is replacedwith an equal amount by weight of a divinyl compound having a molecularweight in the range of about 220 to about 650 and formed by firstreacting a monoepoxide with an alphabeta olefinically unsaturatedmonocarboxylic acid selected from acrylic acid and methacrylic acid andsubsequently reacting the resultant ester condensation product with avinyl unsaturated acyl halide.

26. A paint in accordance with claim 14 wherein an amount up to but lessthan 50% of said tetravinyl compound is replaced with an equal amount byweight of a divinyl compound having a molecular weight in the range ofabout 220 to about 650 and formed by first reacting a monoepoxide withan alpha-beta olefinically unsaturated monocarboxylic acid selected fromacrylic acid and methacrylic acid and subsequently reacting theresulting ester condensation product with a vinyl unsaturated acylhalide.

27. In a method for painting a substrate wherein a film-forming solutionis applied as a paint film to a surface of said substrate andcrosslinked thereon by exposing the coated surface to ionizingradiation, the improvement wherein said film-forming solution, exclusiveof nonpolymerizable solvents, pigments and particulate mineral filler,consists essentially of a film-forming solution of about 20 to about 90parts by weight of an alpha-beta olefinically unsaturated resin havingmolecular weight in excess of about 1,000 and about to about 10 parts byweight of a tetravinyl compound formed by first reacting one molar partof a diepoxide with two molar parts of an alpha-beta olefinicallyunsaturated monocarboxylic acid selected from acrylic acid andmethacrylic acid and subsequently reacting the resultant divinyl estercondensation product with two molar parts of a vinyl unsaturated acylhalide.

28. An article of manufacture comprising in combination a substrate anda polymerized coating of paint formed upon an external surface thereofby applying to said surface a film of substantially even depth of afilm-forming solution which, exclusive of nonpolymerizable solvents,pigments and particulate mineral filler, consists essentially of about20 to about parts by weight of an alpha-beta olefinically unsaturatedresin having molecular weight in the range of about 1,000 to about20,000 and about 80 to about 10 parts by weight of a tetravinyl compoundformed by first reacting one molar part of a diepoxide with two molarparts of an alpha-beta olefinically unsaturated monocarboxylic acidselected from acrylic acid and methacrylic acid and subsequentlyreacting the resultant divinyl ester condensation product with two molarparts of a vinyl unsaturated acyl halide, and cross-linking said filmupon said surface with ionizing radiation.

References Cited UNITED STATES PATENTS 9/1969 Jernigan 260-836X ALFREDL. LEAVITT, Primary Examiner J. H. NEWSOME, Assistant Examiner US. Cl.X.R.

l17138.8, 161; 204l59.l5, 159.16; 260-410.6, 475, 485, 486, 835, 836,857

